From: David Ahern <dsahern@gmail.com>
Date: Tue, 31 Jul 2012 04:31:35 +0000 (-0600)
Subject: perf kvm top: Limit guest kernel info message to once
X-Git-Tag: firefly_0821_release~3680^2~2241^2^2~1
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6b118e92cc78ccef7b54a296158d4738fd377bcc;p=firefly-linux-kernel-4.4.55.git

perf kvm top: Limit guest kernel info message to once

'perf kvm top' shows a continual flurry of:
    Can't find guest [5201]'s kernel information

if it can't find the guest info and with a lot of VMs running a user has no
chance of reading them all. Limit message to once per guest.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1343709095-7089-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 34096275a7b5..68cd61ef6ac5 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -38,6 +38,7 @@
 #include "util/cpumap.h"
 #include "util/xyarray.h"
 #include "util/sort.h"
+#include "util/intlist.h"
 
 #include "util/debug.h"
 
@@ -706,8 +707,16 @@ static void perf_event__process_sample(struct perf_tool *tool,
 	int err;
 
 	if (!machine && perf_guest) {
-		pr_err("Can't find guest [%d]'s kernel information\n",
-			event->ip.pid);
+		static struct intlist *seen;
+
+		if (!seen)
+			seen = intlist__new();
+
+		if (!intlist__has_entry(seen, event->ip.pid)) {
+			pr_err("Can't find guest [%d]'s kernel information\n",
+				event->ip.pid);
+			intlist__add(seen, event->ip.pid);
+		}
 		return;
 	}